create or replace function get_total_time (p_out_time date, p_in_time date)
  return varchar2 is
  v_total_time varchar2(1000);
begin
  select lpad((trunc((p_out_time - p_in_time)) * 24), 2,0)||':'
           into v_total_time
    from dual;
  return v_total_time;
end;

SQL> create or replace function get_total_time (p_out_time date, p_in_time date)
  2    return varchar2 is
  3  begin
  4    return to_char((p_out_time-p_in_time)*24,'fm00')||':';
  5  end;
  6  /

Function created.

SQL> select get_total_time(sysdate+3/24,sysdate) hh from dual;
HH
-------------------------------------------------------------------
03:

select lpad((trunc((p_out_time - p_in_time)) * 24), 2,0)||':'||
                  trunc(mod((sysdate - to_Date('09-nov-2015 09:11:04',
                                      'dd-mon-rrrr hh24:mi:ss')) * 24 * 60,
                   60)) || ':' ||
         trunc(mod((sysdate - to_Date('09-nov-2015 09:11:04',
                                      'dd-mon-rrrr hh24:mi:ss')) * 24 * 60 * 60,
                   60))
    from dual;

SQL> with test as
  2    (select to_date('09.11.2015 11:33', 'dd.mm.yyyy hh24:mi') date_out,
  3            to_date('09.11.2015 10:23', 'dd.mm.yyyy hh24:mi') date_in
  4     from dual
  5    )
  6  select date_out - date_in result_1,
  7         trunc(date_out - date_in) result_2,
  8         trunc(date_out - date_in) * 24 result_3,
  9         lpad(trunc(date_out - date_in) * 24, 2, 0) result_4
 10  from test;

  RESULT_1   RESULT_2   RESULT_3 RE
---------- ---------- ---------- --
,048611111          0          0 00

SQL>